Sealing device for the needle bearing of a universal joint journal pin

ABSTRACT

Sealing device for needle bearings of a universal joint journal pin which is carried by a spider member and is receivable in a bearing bushing press-fitted into a leg of a universal joint fork, the bearing bushing having a free end face with an outer terminal edge, includes a sealing ring of elastomeric material mounted on the journal pin adjacent the spider member proper, said sealing ring having a substantially V-shaped cross section and being formed with one sealing lip abutting the spider member and another sealing lip sealingly engaging the free end face of the bearing bushing; and a ring of synthetic material having a substantially L-shaped cross section and formed with a radially directed leg seated with prestressing on said sealing ring between said sealing lips thereof, and a leg extending axially parallel and engaging the bearing bushing for protecting the seal between said other sealing lip and the bearing bushing against penetration by water and dust, said axially parallel leg being of predetermined diameter so that the inner terminal edge thereof engages with prestressing the outer terminal edge of the bearing bushing.

United States Patent [1 1 Schultenkamper SEALING DEVICE FOR THE NEEDLEBEARING OF A UNIVERSAL JOINT JOURNAL PIN [75] Inventor JosefSchultenkamper, Essen,

Germany [73] Assignee: Gelenkwel lenl a u gmlifl, Essen,

, ,QFEP UY [22] Filed: Dec. 15, 1970 211 Appl. No.: 98,265

Primary Examiner-Edward G. Favors Att0rney-Curt M. Avery, Arthur J.Wilfond, Herbert L. Lerner and Daniel J. Tick Dec. 18, 1973 [5 7]ABSTRACT Sealing device for needle bearings of a universal joint journalpin which is carried by a spider member and is receivable in a bearingbushing press-fitted into a leg of a universal joint fork, the bearingbushing having a free end face with an outer terminal edge, includes asealing ring of elastomeric material mounted on the journal pin adjacentthe spider :member proper, said sealing ring having a substantiallyV-shaped cross section and being formed with one sealing lip abuttingthe spider member and another sealing lip sealingly engaging the freeend face of the bearing bushing; and a ring of synthetic material havinga substantially L-shaped cross section and formed with a radiallydirected leg seated with prestressing on said sealing ring between saidsealing lips thereof, and a leg extending axially parallel and engagingthe bearing bushing for protecting the seal between said other sealinglip and the bearing bushing against penetration by water and dust, saidaxially parallel leg being of predetermined diameter so that the innerterminal edge thereof engages with prestressing the outer terminal edgeof the bearing bushing.

7 Claims, 2 Drawing; Figures PATENTED DEC] 8 I975 FIG.

SEALING DEVICE FOR THE NEEDLE BEARING OF A UNIVERSAL JOINT JOURNAL PINThe invention relates to sealing device for the needle bearing of auniversal joint journal pin.

In the case of journal shafts of relatively small diameter, as are foundin the steering shaft or the universal shaft of private motor vehicles,deepdrawn sheetmetal bearing bushings are used to an increasing extentin the universal joints for the bearing bushings of the needle bearingsof the journal pin instead of solid bushings. These deep-drawn bearingbushings are thinwalled and have a rounded outer terminal edge producedwhen forming the necessary flanging of the end thereof to provide arunway or raceway rim for the needles. This rounded outer terminal edgehas been the cause of considerable difficulty in providing adequatesealing between the spider member and the journal pins carried thereby,on the one hand, and the bearing bushing, on the other hand.

A sealing device has become known heretofore for needle bearing bushingsof deep-drawn. sheet metal which includes a sealing ring of elastomericmaterial prestressedly mounted on a journal pin carried by a spidermember. The sealing ring has a V-shaped cross section and is formed withtwo sealing lips, one of which provides a seal with respect to the endface of a bearing bushing which has been press-fitted into a leg of auniversal joint fork. Also included in the known sealing device is acover ring having an L-shaped cross section and formed with a radiallydirected leg disposed between the other sealinglip of the sealing ringand the journal pin. The cover ring is also formed with a leg extendingaxially parallel and terminating at a location spaced from the bearingbushing. The axially parallel leg is supposed to protect the sealbetween the other sealing lip of the sealing 'ring and the end face ofthe bearing bushing against penetration by dirt and water. Since theknown cover ring has a clearance with re spect to the bearing bushing,it is forced radially outwardly by centrifugal force when the universaljoint rotates at high rotary speed. The cover ring then comes intoengagement with the bearing bushing and can then fulfill the proposedfunction thereof of preventing penetration by dirt and water; however,the other sealing lip of'the sealing ring is simultaneously morestrongly prestressed to an undesired extent.

A sealing device is known for a solid bearing bushing which includes asealing ring of elastomeric material prestressedly mounted on a journalpin carried by a spider member, The sealing ring has a V-shaped crosssection and is formed with one sealing lip abutting the spider memberand another sealing lip providing a seal with respect to the end face ofthe bearing bushing. Als includedin this known sealing device for asolid bearing bushing is a cover ring of synthetic material having anL-shaped cross section and formed with a radially directed legprestressedly seated on the sealing ring between the sealing lipsthereof, and a leg extending axially parallel which protects the sealbetween the other sealing lip and the bearing bushing againstpenetration by water and dirt, due to the fact that the axially parallelleg comes into engagement with a shoulder extending beyond the end faceof the solid bearing bushing. With this known sealing device, thesynthetic ring protects the seal between the other sealing lip and thebearing bushing, at all rotary speeds of the universal joint and alsowhen the joint is at rest, against penetratrifugal force. A shoulder isunable to be provided,

however, for a bearing bushing formed of deep-drawn sheet metal.

It is accordingly an object of the invention to provide sealing devicefor the needle bearings of a universal joint jounral pin which avoidsthe disadvantages of the heretofore known devices of this general type.

More specifically, it is an object of the invention to provide suchsealing device which will ensure the prevention of penetration of dirtand water through the seal formed between the sealing lip of the sealingring and the bearing bushing withoutadditionally prestressing thesealing ring.

With the foregoing and other objects in view, there is provided inaccordance with the invention, sealing device for needle bearings of auniversal joint journal pin which is carried by a spider member and isreceivable in a bearing bushing pressfitted into a leg of a universaljoint fork, the bearing bushing having a free end face with an outerterminal edge, comprising a sealing ring of elastomeric material mountedon the journal pin adjacent the spider member proper, the sealing ringhaving a substantially V-shaped cross section and being formed with onesealing lip abutting the spider member and another sealing lip sealinglyengaging the free end face of the bearing bushing; and a ring ofsynthetic material having a substantially L-shaped cross section andformed with a radially directed leg seated with prestressing on thesealing ring between the sealing lips thereof, and a leg extendingaxially parallel and engaging the bearing bushing for protecting theseal between the other sealing lip and the bearing bushing againstpenetration by water and dust, the axially parallel leg being ofpredetermined diameter so that the inner terminal edge thereof engageswith prestressing the outer terminal edge of the bearing bushing.

In accordance with a further feature of the invention, when the bearingbushing is formed of deep'drawn sheet metal and the outer terminal edgeof the free end face thereof is rounded, the inner terminal edge of theaxially parallel leg is formed with a rounded surface prestressedlyengaging the rounded outer terminal edge of the free end face.

In accordance with other features of the invention, when the outerterminal edge of the free end face of the bearing bushing is formedeither with a conical chamfer or a rounded surface, the inner terminaledge of the axially parallel leg prestressedly engages the chamfer orthe rounded surface, as the case may be.

In accordance with still further features of the invention, the innerterminal edge of the axially parallel leg is formed with a chamfer or arounded surface.

Due to the fact that the inner terminal edge of the axially parallel legof the synthetic ring prestressedly abuts the chamfer or rounded surfaceof the bearing bushing, an axial force exists which forces the onesealing lip more strongly toward the spider member, and the syntheticring cannot be forced radially outwardly under the effect of centrifugalforce, and the other sealing lip, which forms a seal with the bearingbushing that turns reciprocatingly with respect to the same, can beadditionally prestressed in an undesired manner. The

other effect is that due to the close contact between the inner terminaledge of the free leg of the synthetic ring and the bearing bushing, theouter or other sealing lip is effectively protected against penetrationby water and dirt and that this close contact is automatically adjustedas long as there still is a prestressing force between the syntheticring and the bearing bushing. Furthermore, the ring of L-shaped crosssection also protects the elastomeric or rubber sealing ring when theshaft is being varnished or painted. ln the case of the first-mentionedheretofore known sealing device, varnish or lacquer can penetrate to therubber sealing ring which often causes the latter to adhere tightly tothe bearing bushing so that the sealing device is no longer movable withrespect to the bearing bushing but rather with respect to the journalpin and to the spider member. 1

Other features which are considered as characteristic for the inventionare set forth in the appended claims.

Although the invention is illustrated and described herein as embodiedin sealing device for the needle bearings of a universal joint journalpin, it is nevertheless not intended to be limited to the details shown,since various modifications and structural changes may be made thereinwithout departing from the spirit of the invention and within the scopeand range of equivalents of the claims.

The construction and method of operation of the invention, however,together with additional objects and advantages thereof will be bestunderstood from the following description of specific embodiments whenread in connection with the accompanying drawing, in which:

FIG. 1 is a longitudinal view of one half ofa universal joint with ajournal pin inserted therein; and

H6. 2 is an enlarged fragmentary view of FIG. 1 showing details of theregion thereof enclosed in the circle ll.

Referring now to the drawing, there is shown a fork l of a universaljoint, which can be secured by means of a flange 1' to one section of auniversal shaft or to a shaft projecting from a transmission. The otherfork of the universal joint, which is connected to the fork 1 by aspider member 2 carrying journal pins 6, has been omitted in theinterest of clarity.

A hearing bushing 3 deep-drawn of sheet metal is pressed into each legof the fork l, and is closed at the outer end thereof by a respectivecover 4. If the bearing bushing has a relatively small diameter, insteadof a special cover, the bushing is provided with a'base integraltherewith. Needles 5 of a cageless bearing for one of the pins 6 on thespider member 2 are disposed within the bearing bushing 3.

The sealing device of the invention for each of the needle bearings 5 isshown most clearly in FIG. 2. The bearing bushing 3, deep-drawn of sheetmetal, is provided with an inwardly directed flange 30 at the outer endthereof to form a runway rim for the needles 5, whereby the outerterminal edge of the bearing bushing 3 is necessarily rounded. Betweenthe bearing bushing 3 and the spider 2, there is firmly seated withprestressing, on the pin 6 extending from the spider 2, a rubber sealingring 7 of V-shaped cross section. The sealing ring 7 is formed with aninner sealing lip 7a that is prestressed against the spider 2 proper.The sealing ring 7 is also formed with an outer sealing lip 7b whichabuts the end face 3b located at the flange 3a of the bearing bushing 3,in order to seal the needle bearing 5 from the outside. A ring 8 ofsynthetic material and having an L-shaped cross section with legs 8a and8b defining a right angle therebetween' in unstressed condition thereof,is mounted on and coaxial with the sealing ring 7. The annular leg 8b isseated with radial prestressing on the sealing ring 7 between thesealing lips 7a and 7b. The other leg 8a extends axially parallel to thering 8 and, due to a suitably selected diameter therefor, engages by aninner terminal edge thereof, with prestresssing, the rounded outerterminal edge of the bearing bushing 3. The inner terminal edge 80 ofthe ring 8 is slightly chamfered so that it provides contact on anannular surface with the bearing bushing 3, and effectively protects thesealing lip .7b against penetration of dirt and water. Instead of beingprovided with a chamfer, the terminal edge 8c can be given a roundedsurface.

The aforedescribed sealing device is capableof being employedadvantageously with a'massive bearing bushing as well as with a bearingbushing deep-drawn of sheet metal, because a rounded or chamferedterminal edge can be produced in the massive bearing bushing in a muchsimpler manner than a shoulder. Especially when the terminal edge of thebearing bushing is chamfered, the inner terminal edge of the axiallyparallel leg of the synthetic ring can be provided with a roundedsurface.

I claim:

1. Sealing device for needle bearings of a universal joint journal pinwhich is carried by a spider member and is receivable in a bearingbushing having a generally cylindrical outer wall and which ispress-fitted into a leg of a universal joint fork, the bearing bushinghaving a free end face and a transitional surface between said free endface and said outer wall extending at least partly in radial direction,the sealing device comprising a sealing ring of elastomeric materialmounted on the journal pin adjacent the spider member proper, saidsealing ring having a substantially V-shaped cross section and beingformed with one sealing lip abutting the spider member and anothersealing lip sealingly engaging the free end face of the bearing bushing;and a ring of synthetic material having a substantially L-shaped crosssection and formed with a radially directed leg seated with prestressingon said sealing ring between said sealing lips thereof, and a legextending axially parallel and engaging the bearing bushing forprotecting the seal between said other sealing lip and the bearingbushing against penetration by water and dust, said axially parallel legbeing of predetermined diameter so that the inner terminal edge thereofengages with axially directed prestressing said transitional surface ofthe bearing bushing.

2. Sealing device for needle bearings of a universal joint journal pinwhich is carried by a spider member and is receivable in a bearingbushing having a generally cylindrical outer wall and which ispress-fitted into a leg of a universal joint fork, the bearing bushinghaving a free end face and a transitional surface between said free endface and said outer wall comprising a sealing ring of elastomericmaterial mounted on the journal pin adjacent the spider member proper,said sealing ring having a substantially V-shaped cross section andbeing formed with one sealing lip abutting the spider member and anothersealing lip sealingly engaging .the free end face of the bearingbushing; and a ring of synthetic material having a substantiallyL-shaped cross section and formed with a radially directed leg seatedwith prestressing on said sealing ring between said sealing lipsthereof, and a leg extending axially parallel and engaging the bearingbushing for protecting the seal between said other sealing lip and thebearing bushing against penetration by water and dust, said axiallyparallel leg being of predetermined diameter so that the inner terminaledge thereof engages with prestressing said transitional surface of thebearing bushing, whereby an axial component of force is biasinglyapplied to said ring of synthetic material, said transitional surface ofthe bearing bushing being formed with a conical chamfer, and said innerterminal edge of said axially parallel leg prestressingly engaging saidchamfer.

3. Sealing device for needle bearings of a universal joint journal pinwhich is carried by a spider member and is receivable in a bearingbushing having a generally cylindrical outer wall and which ispress-fitted into a leg of a universal joint fork, the bearing bushinghaving a free end face and a transitional surface between said free endface and said outer wall comprising a sealing ring of elastomericmaterial mounted on the journal pin adjacent the spider member proper,said sealing ring having a substantially V-shaped cross section andbeing formed with one sealing lip abutting the spider member and anothersealing lip sealingly engaging the free end face of the bearing bushing;and a ring of synthetic material having a substantially L-shaped crosssection and formed with a radially directed leg seated with prestressingon said sealing ring between said sealing lips thereof, and a legextending axially parallel and engaging the bearing bushing forprotecting the seal between said other sealing lip and the bearingbushing against penetration by water and dust, said axially parallel legbeing of predetermined diameter so that the inner terminal edge thereofengages with prestressing said transitional surface of the bearingbushing, whereby an axial component of force is biasingly applied tosaid ring of synthetic material, said transitional surface of thebearing bushing being formed with a rounded surface, and said innerterminal edge of said axially parallel leg prestressedly engaging saidrounded surface.

4. Sealing device for needle bearings of a universal joint journal pinwhich is carried by a spider member and is receivable in a bearingbushing having a gener' ally cylindrical outer wall and which ispress-fitted into a leg of a universal joint fork, the bearing bushinghaving a free end face and a transitional surface between said free endface and said outer wall comprising a sealing ring of elastomericmaterialmounted on the journal pin adjacent the spider member proper,said sealing ring having a substantially V-shaped cross section andbeing formed with one sealing lip abutting the spider member and anothersealing lip sealingly engaging the free end face of the bearing bushing;and a ring of synthetic material having a substantially L-shaped crosssection and formed with a radially directed leg seated withprestressingon said sealing ring between said sealing lips thereof, and a legextending axially parallel and engaging the bearing bushing forprotecting the seal between said other sealing lip and the bearingbushing against penetration by water and dust, said axially parallel legbeing of predetermined diameter so that the inner terminal edge thereofengages with prestressing said transitional surface of the bearingbushing, whereby an axial component of force is biasingly applied tosaid ring of synthetic material, said inner terminal edge of saidaxially leg being formed with a chamfer.

5. Sealing device for needle bearings of a universal joint journal pinwhich is carried by a spider member and is receivable in a bearingbushing having a generally cylindrical outer wall and which ispress-fitted into a leg of a universal joint fork, the bearing bushinghaving a free end face and a transitional surface between said free endface and said outer wall comprising a sealing ring of elastomericmaterial mounted on the journal pin adjacent the spider member proper,said sealing ring having a substantially V-shaped cross section andbeing formed with one sealing lip abutting the spider member and anothersealing lip sealingly engaging the free end face of the bearing bushing;and a ring of synthetic material having a substantially Lshaped corsssection and formed with a radially directed leg seated with prestressingon said sealing ring between said sealing lips thereof, and a legextending axially parallel and engaging the bearing bushing forprotecting the seal between said other sealing lip'and the bearingbushing against penetration by water and dust, said axially parallel legbeing of predetermined diameter so that the inner terminal edge thereofengages with prestressing said transitional surface of the bearingbushing, whereby an axial component of force is biasingly applied tosaid ring of synthetic material, said inner terminal edge of saidaxially parallel leg being formed with a rounded surface.

6. Sealing device for needle bearings of a universal joint journal pinwhich is carried by a spider member and is receivable in a bearingbushing having a generally cylindrical outer wall and which ispress-fitted into a leg of a universal joint fork, the bearing bushinghaving afree end face and a transitional surface between said free endface and said outer wall comprising a sealing ring of elastomericmaterial mounted on the journal pin adjacent the spider member proper,said sealing ring having a substantially V-shaped cross section andbeing formed with one-sealing lip abutting the spider member and anothersealing lip sealingly engaging the free end face of the bearing bushing;and a ring of synthetic material having a substantially L-shaped crosssection and formed with a radially directed leg seated with prestressingon said sealing ring between said sealing lips thereof, and a legextending axially parallel and engaging the bearing bushing forprotecting the seal between said other sealing lip and the bearingbushing against penetration by water and dust, said axially parallel legbeing of predetermined diameter so that the inner terminal edge thereofengages with prestressing said transitional surface of the bearingbushing, whereby an axial component of force is biasingly applied tosaid ring of synthetic material, the bearing bushing being formed ofdeep-drawn sheet metal and said transitional surface being rounded, saidinner terminal edge of said axially parallel leg being formed with arounded surface prestressedly engaging the rounded outer transitionalsurface.

7. Sealing device for needle bearings of a universal joint journal pinwhich is carried by a spider member and is receivable in a bearingbushinghaving a generally cylindrical outer wall and which ispress-fitted into a leg of a universal joint fork, the bearing bushinghaving a free end face and a transitional surface between said free endface and said outer wall comprising a sealing ring of elastomericmaterial mounted on the journal pin adjacent the spider member proper,said sealing ring having a substantially V-shaped cross section andbeing formed with one sealing lip abutting the spider member and anothersealing lip sealingly engaging the free end face of the bearing bushing;and a ring of synthetic material having a substantially L-shaped crosssection and formed with a radially directed leg seated with prestressingon said sealing ring between said sealing lips thereof, and a legextending axially parallel and engaging the bearing bushing forprotecting the seal between said other sealing lip and the bearingbushing against penetration by water and dust, said axially parallel legbeing of predetermined diamter so that the inner terminal edge thereofengages with prestressing said transitional surface of the bearingbushing, whereby and axial component of force is biasingly applied tosaid ring of synthetic material, said transitional surface extending atan acute angle relative to said leg of said universal joint, said innerterminal edge of said axially parallel leg biasingly engaging saidtransitional surface at said acute angle whereby an axially directedforce is biasingly exerted by said ring of synthetic material understand still and operating conditions of said universal joint.

1. Sealing device for needle bearings of a universal joint journal pinwhich is carried by a spider member and is receivable in a bearingbushing having a generally cylindrical outer wall and which ispress-fitted into a leg of a universal joint fork, the bearing bushinghaving a free end face and a transitional surface between said free endface and said outer wall extending at least partly in radial direction,the sealing device comprising a sealing ring of elastomeric materialmounted on the journal pin adjacent the spider member proper, saidsealing ring having a substantially V-shaped cross section and beingformed with one sealing lip abutting the spider member and anothersealing lip sealingly engaging the free end face of the bearing bushing;and a ring of synthetic material having a substantially L-shaped crosssection and formed with a radially directed leg seated with prestressingon said sealing ring between said sealing lips thereof, and a legextending axially parallel and engaging the bearing bushing forprotecting the seal between said other sealing lip and the bearingbushing against penetration by water and dust, said axially parallel legbeing of predetermined diameter so that the inner terminal edge thereofengages with axially directed prestressing said transitional surface ofthe bearing bushing.
 2. Sealing device for needle bearings of auniversal joint journal pin which is carried by a spider member and isreceivable in a bearing bushing having a generally cylindrical outerwall and which is press-fitted into a leg of a universal joint fork, thebearing bushing having a free end face and a transitional surfacebetween said free end face and said outer wall comprising a sealing ringof elastomeric material mounted on the journal pin adjacent the spidermember proper, said sealing ring having a substantially V-shaped crosssection and being formed with one sealing lip abutting the spider memberand another sealing lip sealingly engaging the free end face of thebearing bushing; and a ring of synthetic material having a substantiallyL-shaped cross section and formed with a radially directed leg seatedwith prestressing on said sealing ring between said sealing lipsthereof, and a leg extending axially parallel and engaging the bearingbushing for protecting the seal between said other sealing lip and thebearing bushing against penetratiOn by water and dust, said axiallyparallel leg being of predetermined diameter so that the inner terminaledge thereof engages with prestressing said transitional surface of thebearing bushing, whereby an axial component of force is biasinglyapplied to said ring of synthetic material, said transitional surface ofthe bearing bushing being formed with a conical chamfer, and said innerterminal edge of said axially parallel leg prestressingly engaging saidchamfer.
 3. Sealing device for needle bearings of a universal jointjournal pin which is carried by a spider member and is receivable in abearing bushing having a generally cylindrical outer wall and which ispress-fitted into a leg of a universal joint fork, the bearing bushinghaving a free end face and a transitional surface between said free endface and said outer wall comprising a sealing ring of elastomericmaterial mounted on the journal pin adjacent the spider member proper,said sealing ring having a substantially V-shaped cross section andbeing formed with one sealing lip abutting the spider member and anothersealing lip sealingly engaging the free end face of the bearing bushing;and a ring of synthetic material having a substantially L-shaped crosssection and formed with a radially directed leg seated with prestressingon said sealing ring between said sealing lips thereof, and a legextending axially parallel and engaging the bearing bushing forprotecting the seal between said other sealing lip and the bearingbushing against penetration by water and dust, said axially parallel legbeing of predetermined diameter so that the inner terminal edge thereofengages with prestressing said transitional surface of the bearingbushing, whereby an axial component of force is biasingly applied tosaid ring of synthetic material, said transitional surface of thebearing bushing being formed with a rounded surface, and said innerterminal edge of said axially parallel leg prestressedly engaging saidrounded surface.
 4. Sealing device for needle bearings of a universaljoint journal pin which is carried by a spider member and is receivablein a bearing bushing having a generally cylindrical outer wall and whichis press-fitted into a leg of a universal joint fork, the bearingbushing having a free end face and a transitional surface between saidfree end face and said outer wall comprising a sealing ring ofelastomeric material mounted on the journal pin adjacent the spidermember proper, said sealing ring having a substantially V-shaped crosssection and being formed with one sealing lip abutting the spider memberand another sealing lip sealingly engaging the free end face of thebearing bushing; and a ring of synthetic material having a substantiallyL-shaped cross section and formed with a radially directed leg seatedwith prestressing on said sealing ring between said sealing lipsthereof, and a leg extending axially parallel and engaging the bearingbushing for protecting the seal between said other sealing lip and thebearing bushing against penetration by water and dust, said axiallyparallel leg being of predetermined diameter so that the inner terminaledge thereof engages with prestressing said transitional surface of thebearing bushing, whereby an axial component of force is biasinglyapplied to said ring of synthetic material, said inner terminal edge ofsaid axially leg being formed with a chamfer.
 5. Sealing device forneedle bearings of a universal joint journal pin which is carried by aspider member and is receivable in a bearing bushing having a generallycylindrical outer wall and which is press-fitted into a leg of auniversal joint fork, the bearing bushing having a free end face and atransitional surface between said free end face and said outer wallcomprising a sealing ring of elastomeric material mounted on the journalpin adjacent the spider member proper, said sealing ring having asubstantially V-shaped cross section and being formed with one sealinglip abutting the spider Member and another sealing lip sealinglyengaging the free end face of the bearing bushing; and a ring ofsynthetic material having a substantially L-shaped corss section andformed with a radially directed leg seated with prestressing on saidsealing ring between said sealing lips thereof, and a leg extendingaxially parallel and engaging the bearing bushing for protecting theseal between said other sealing lip and the bearing bushing againstpenetration by water and dust, said axially parallel leg being ofpredetermined diameter so that the inner terminal edge thereof engageswith prestressing said transitional surface of the bearing bushing,whereby an axial component of force is biasingly applied to said ring ofsynthetic material, said inner terminal edge of said axially parallelleg being formed with a rounded surface.
 6. Sealing device for needlebearings of a universal joint journal pin which is carried by a spidermember and is receivable in a bearing bushing having a generallycylindrical outer wall and which is press-fitted into a leg of auniversal joint fork, the bearing bushing having a free end face and atransitional surface between said free end face and said outer wallcomprising a sealing ring of elastomeric material mounted on the journalpin adjacent the spider member proper, said sealing ring having asubstantially V-shaped cross section and being formed with one sealinglip abutting the spider member and another sealing lip sealinglyengaging the free end face of the bearing bushing; and a ring ofsynthetic material having a substantially L-shaped cross section andformed with a radially directed leg seated with prestressing on saidsealing ring between said sealing lips thereof, and a leg extendingaxially parallel and engaging the bearing bushing for protecting theseal between said other sealing lip and the bearing bushing againstpenetration by water and dust, said axially parallel leg being ofpredetermined diameter so that the inner terminal edge thereof engageswith prestressing said transitional surface of the bearing bushing,whereby an axial component of force is biasingly applied to said ring ofsynthetic material, the bearing bushing being formed of deep-drawn sheetmetal and said transitional surface being rounded, said inner terminaledge of said axially parallel leg being formed with a rounded surfaceprestressedly engaging the rounded outer transitional surface. 7.Sealing device for needle bearings of a universal joint journal pinwhich is carried by a spider member and is receivable in a bearingbushing having a generally cylindrical outer wall and which ispress-fitted into a leg of a universal joint fork, the bearing bushinghaving a free end face and a transitional surface between said free endface and said outer wall comprising a sealing ring of elastomericmaterial mounted on the journal pin adjacent the spider member proper,said sealing ring having a substantially V-shaped cross section andbeing formed with one sealing lip abutting the spider member and anothersealing lip sealingly engaging the free end face of the bearing bushing;and a ring of synthetic material having a substantially L-shaped crosssection and formed with a radially directed leg seated with prestressingon said sealing ring between said sealing lips thereof, and a legextending axially parallel and engaging the bearing bushing forprotecting the seal between said other sealing lip and the bearingbushing against penetration by water and dust, said axially parallel legbeing of predetermined diamter so that the inner terminal edge thereofengages with prestressing said transitional surface of the bearingbushing, whereby and axial component of force is biasingly applied tosaid ring of synthetic material, said transitional surface extending atan acute angle relative to said leg of said universal joint, said innerterminal edge of said axially parallel leg biasingly engaging saidtransitional surface at said acute angle whereby an axially directeDforce is biasingly exerted by said ring of synthetic material understand still and operating conditions of said universal joint.